# Decoupling of graphene from Ni(111) via oxygen intercalation

## TL;DR

This study demonstrates how oxygen intercalation can effectively decouple graphene from Ni(111), forming a NiO layer that preserves graphene's properties and induces strong p-doping, with insights supported by experimental and theoretical analysis.

## Contribution

It provides a detailed understanding of graphene decoupling from Ni(111) through oxygen intercalation, combining surface science techniques and density-functional theory.

## Key findings

- Graphene is fully decoupled from Ni(111) after oxygen intercalation.
- A NiO antiferromagnetic layer forms at the interface.
- Graphene becomes strongly p-doped with the Dirac point 0.69 eV above Fermi level.

## Abstract

The combination of the surface science techniques (STM, XPS, ARPES) and density-functional theory calculations was used to study the decoupling of graphene from Ni(111) by oxygen intercalation. The formation of the antiferromagnetic (AFM) NiO layer at the interface between graphene and ferromagnetic (FM) Ni is found, where graphene protects the underlying AFM/FM sandwich system. It is found that graphene is fully decoupled in this system and strongly $p$-doped via charge transfer with a position of the Dirac point of $(0.69\pm0.02)$ eV above the Fermi level. Our theoretical analysis confirms all experimental findings, addressing also the interface properties between graphene and AFM NiO.